A conventional automatic transmission includes a planetary gearset, which forms a multi-gear train, and a friction component for changing a gear ratio and torque transmission route in response to the planetary gearset engaging and disengaging with an input shaft and housing of the transmission. Conventional planetary gearsets output a multi-gear ratio in an automatic transmission with more than 5 speeds, thus increasing the driving force at low speeds and improving fuel consumption rate at high speeds.
Also, in order for the planetary gearset to output a multi-gear ratio in an automatic transmission with 5 speeds or greater, a skip shift of more than one stage is necessary. The skip shift, which can change the shift stage for one or more stages during shifting, improves the response during shifting.
However, a 5-3 or 4-2 skip shift in a conventional 5-speed automatic transmission is not a skip shift in the real sense because the 5-3 and 4-2 skip shift are sequentially performed in a 5-4-3 and 4-3-2 pattern, respectively.
In a 5-speed automatic transmission, the 5-3 or 4-2 skip shift is sequentially performed as a result of a hardware feature of the transmission, and more particularly, as a result of a difficulty of simultaneously controlling two engagement components and two disengagement components during the skip shifting.
As a result, there is a drawback in a conventional 5-speed automatic transmission in that the sequential shift rendered during the skip shift lowers the response in comparison with the true meaning of the skip shift.